1. Physics Department, Faculty of Science, Beni-Suef University, Beni Suef, Egypt
2. Physics Department, Faculty of Science, Sana’a University, Sana’a, Yemen
3. Department of Electrical Engineering, University of Malaya, Kuala Lumpur, Malaysia
4. Department of Physics, Faculty of Science and Technology, Airlangga University, Surabaya, Indonesia